Sound-reproducing mechanism



R. ALTMANN' SOUND REPRODUCING MECHANI SM 2 SheerZs-Sheet 2 Filed April 7. 1925 2 INVENTOR BY ATTORNEY Patented Nov. 2, 19256.

PATENT BUIDOLF ALTMANN, 0F BROOKLYN, NEW Y0.

sonnn-anraono'cme macnamsmQ Application filed April 'I, 1926. Serial No; 21,275.

This invention relates to sound re roducing apparatus and has for its main 0 jectto provide a construction, that calrbe easily applied to an alarm clock, so that instead of the ordinary bell alarm a record Wlll be operated.

With this and other objects in view, my invention consists in the construction, combination and arrangement of parts as will be hereinafter more fully described and defined in the appended claims.

In the accompanying drawing. in which record and Fig. 6 a detail view of the es-' capement release mechanism.

(1 denotes the usual cylindrical casing of the time clock, I) the front glass wall thereof, 0 the time pointers, d the time controlled clutch spindle carrying the alarm pointer e, f the stop used in connection with the alarm escapement g andoperated as usual from the clutch spindle (Z. The escapement is of ordinary construction, except that the clapper, which, in ordinary alarm clocks, is car* ried by it, is omitted: This escapement, as usual, cooperates with the ratchet wheel h, which, through a pinion a", meshes with the gear fixed on the spindle 7c actuated fro the alarm operating spring Z.

Thus far the construction is the same as with the usual alarm clock, the clapper and bell being omitted.

The rear wall of the casing a is also omitted and the latter is suitably fixed to a cylindrical flange 10 of a casing 10 of rectangular shape composed of two sections 10, 10 which are suitably hinged together, as at 10", to permit the opening of the casing for winding u the clock, making repairs and for the exc ange of records of the sound re reducing mechanism hereinafter more in ly described. The spindle .70 actuated from the alarm operating spring Z, under the control ofthe escapement g, is somewhat extended rearwardly through the rear Wall ofthe frame m of the time clock mechanism and carries a pinion 11, which meshes with an idler 12 suitably supported on the repr wall of-the frame m. This idler again through an intermediate gear 13 meshes with a pinion 14 fixed on a central horizontal spindle 15 'rotatively supported in the wall of the frame m and projecting from'the rear face thereof a short distance into the casing 10. This central spindle 15 serves to removab-ly support a turntable 16 and a record disc 17 of 'the usual construction. The turn-table and record disc will, as will be understood, be set in rotation through the action of the spring coil Z of the alarm mechanism upon the release of the escapement g, when the stop f, at the proper time, releases said escapement. In the section 10' of the casing 10, I provide the tone arm 18 carrying the usual sound box 19. This tone arm is suspended with its rear wider end from the rear wall of the casing 10 to be capable of swinging in two planes, to wit: in a vertical vplane parallel to the record disc and a vertical plane perpendicular to said disc. The axis for the first named swinging movement of the tone arm is located about vertically above one end of the horizontal diameter of the record disc and the axis for the second movement slightly behind and above the center of gravity of the tone arm and sound box. The distance from the axis of the first named swinging movement to the needle 19' of the sound box or the length of the lever arm is so admeasured'that normally the needle l9' will be about in range with or slightly above or below the center of the rim of the record disc and the circular are described by the needle, when travellin' through the ridges of and across the disc 1% constituting the'record, will be as flat as pos sible, so that very little force will be required to swing the tone arm across the disc in the direction from the rim toward the center thereof.

In the presentexample, the wide rear end' of the tone arm is mounted on a cylindrical smaller in diameter than the diameter of the lltl tone arm at its upper or rear end, so as to afford a small play or a slight swinging movement around said pin in a plane perpendicular to the record disc 17. By such suspension the tone arm, will normally tend to extend in a vertical plane with the needle 19' of the sound box directly opposite the rim of but slightly raised from the record disc or of the record itself,

The sound box may be provided with a rearwardly extending grasp or pin 2% projecting through a circularly curved recess or slot 25 oi the rear wall of the casing 10, and whereby the tone arm may be mannally adjusted to bring it from the rim of the record disc to the starting ridge of the record or to shift it from operative position whenever desired; 7 r

Fixed m and projecting inwardly from the rear wall of the casing "10 at a suitable place below the center of the record disc, is a bracket 26 to which is fixed a resilient horizontal guide27, such as a spring leaf, whose free end is formed to a grasp 2'3 and projects through a slot 28 provided in the opposite side wall of the casing 10. Near its fixed end, this bar is made to slant rearwardly, as at 27". Projecting downwardly from the sound box, is a pin or the like 29 carrying a roller 30, which is adapted to constantly bear on the guide 27. The latter normally is adapted to ress against the roller and to thereby ho d the sound boa projected forwardly, so that its needle 19 will be held against the record plate with a very slight pressure, a pressure just Suficient to cause the needle to follow the undulations of the record, but not enough to prevent it from rising from contact with the record, while in operation; The slanting portion 27' of the spring guide, however, will permit the sound box, when arriving at the end portion of the record, to swing back with the tone arm into its normal position in which its needle 19' will be out of contact with the record. In this position, the

sound box will remain, after the needle has reached the end position on the record disc.

until the usenby means or the grasp 27., bends the guide 27 slightly rearwardly sufficiently to permit the roller to pass from the slanting portion 27 onto the main portion of the guide and to roll over it, under the gravity action of the tone arm, which will now be permitted to swing back into normal position. In order that the needle 19 be out of contact with the record disc, when the latter is not in operation, or at least until after starting the record, the latter has assumed sufficient speed, I provide the follow ing mechanism:

- Slidably supported, as at 31', on the rear wall of the frame m, is a horizontal bar 31,

which extends from the center toward the rim across the rear face of the turn-table.

nooaeea is provided on the sound box, which is adapted in normal position to bear against'the hookedend 31 of the bar 31.. The opposite end of the latter is adapted to be actuated from a cam 33 mounted on a spindle 34 driven from the pinion 15, which meshes with a relatively larger gear 35 on said spindle 34, the ratio between said pinion and gear being suitable to permit two or more'full revolutions of the record disc for each revolution of the cam. Thus when the bar 31 is in operative position and the rec ord is started, the cam 33, after say two full revolutions of the record disc, I will act against said bar shifting it laterally suficiently to release the sound box, which, by the spring guide 27, will then be brought into contact with the record. The extreme end 31'. of the hooked portion 31 may be gradually curved toward the record plate, so that, as the bar 31 is shifted by the cam 33 into inoperative position, it will gradually release the sound box preventing the needle from being thrust abruptly into contact with the record. The bar 31 is pro vided with a gra or pin 36, which projects through a slot 3 in the side wall oi'the casing, whereby said bar can be brought into operative position, after the record has been finished and before the tone arm is permitted to swing baclr into starting position.

in order to arrest the sound reproducing mechanismn when its operation is not desired, while the clock continues to work, I provide a slidable bolt 38, which may be suitably borne in the knob n, which usually carries the ring or grasp o of the clock. This bolt, at its inner or lower end, is adapted to coopcrate with a pin 39 projecting from the ratchet wheel it controlled by the escapement 7. Thus when the bolt 38 and pin 39 are in engagement, the release of the escapement 9 from its stop f will be inefiective and the spring Z will remain locked.

0n the other hand, if it is desired to use the sound reproducing mechanism out of time. the escapement may be released by hand by means of a pin 40 projecting through the top oi'the casing 12 into the clock mechanism and formed with a cam or wedge-shaped member 41, which."when the pin is shifted longitudinally, will engage the stop f and move it out of engagement with the escapernent g.

It is, of course, understood that the dif ferent mechanisms and means described for the operation of the sound reproducing apparatus may be varied in many ways by neonate those skilled inthe art. I, therefore, do not wish to limit myself to the details described and shown. I

W' hat I claim is 1. In a sound-reproducing mechanism, the combination with a vertically ,disposed' revoluble record disc of a tone arm suspended to swing in a vertical plane parallel to said record disc and carrying a sound box normally tending to be raised from the record disc, means for positively retaining the sound box in operative position and means for holding the sound box against coming in contact with the record disc during a certain number of revolutions of the latter after starting.

2. In a sound reproducing mechanism, the combination with a Vertically disposed revoluble record disc of a tone arm suspended to swin in vertical plane parallel to said record is: and carrying a sound box normally tending to be raised from the record disc, means for positively retaining .the sound box in operative position and automatically controlled means for holding the sound box a ainst coming in contact with saidrecord dlsc during a certain number of revolutions of the latter after star ing.

3. In a phonograph, an automatically ter in contact with said record, while in operation, and means for holding the sound box out of contact with the record disc dur ing a certain number of revolutions of the latter after starting. v

4. In a sound reproducing mechanism, the combination with a vertically disposed revoluble. record disc, of a tone arm suspended to swing in a vertical plane parallel to said record disc and carrying a sound boxnormally tending to be raised from the record disc, means for positively retaining the sound box in operative position and automatically controlled cam operated means for holding the sound box against coiningin contact with said record disc during a certain'number of revolutions of the latter after starting.

In testimony whereof I afiix my signature.

armors ALTMANN. 

